Approximately 1,857 of these carbines were manufactured by Robbins & Lawrence in Windsor, Vermont, circa 1852-1855. Marked with "C. SHARPS/PATENT/1848" and serial number "438" on the receiver, "EDWARD MAYNARD/PATENTEE/1845" on the outside of the tape primer cover and "458" faintly hand numbered on the inside. The bottom of the frame and left breech end of the barrel both marked "R.S.L.", which was the mark of Richard S. Lawrence, Superintendent of Robbins & Lawrence; with whom Sharps had contracted for the manufacture of his guns after finding that A. S. Nippes did not have the capacity to turn out the large quantities that would be required by the government orders Sharps was hoping to get. The R.S.L. mark was not used on all of the guns made by Robbins & Lawrence, generally being reserved for special order or select guns. These Model 1851's are distinguishable by the hammer which is mounted inside the lock, and were the first model of Sharps carbines issued to the U.S. military, though this one bears no military markings. It has the standard markings and features. Brass blade front and flip up "squirrel ear" rear sight. A long sling ring bar runs from the left side of the receiver to the brass barrel band. Fitted with a walnut two piece stock and brass buttplate.